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Not yet. We don't know when we will know it, but I think it's a key point:
1. He is a "maggot". I continue to wonder why Guwon was in the place where the catastrophe began and how he hadn't any damage when he was buried in a building. What exactly would these marks be in this case? If there were necrotic arms, I say that the MC himself would notice it?
2. Guwon made his marks on purpose, so he can pass by unnoticed among the "maggots", which makes me think that he really knows what he's doing. I noticed that many times he acted very "silly" towards the MC, but in a second his expression was serious, as if he was testing MC. (Episode 6 for example)
Now, what are your theories about what is happening?
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I like it. I think your theory and the theory in the comment below may be getting close to the truth. But why Guwon as a subject and who he is I have no idea. I mean, everyone respects him but also fears him. He seems to have a below normal IQ (as you said possibly being an experiment like Frankenstein or the origin of the maggots) and at the same time he is the village chief lol.
I'm intrigued by the open door rule. Is it because Guwon keeps an eye on the inhabitants, or to kill whoever he considers useless without them being in the house?
Have they explained why he has black markings and a cut on his neck yet?? I wanna know whyyyy is he half zombie or smth